1. Technical Field
The present invention relates to an electrostatic latent image developing toner (hereafter also referred to as an electrophotographic toner) and methods of producing such a toner. The invention also relates to electrostatic latent image developers obtained using these production methods.
2. Related Art
In recent years, in the field of electrophotographic toner production, the desire to reduce environmental impact, as typified by LOHAS, has lead to increased demands for greater energy conservation, in addition to the more conventional demands for improvements in image quality and higher productivity.
In order to satisfy demands for these types of electrophotographic toners, conventional mix-and-grind methods, in which the resin is subjected to melt mixing at a high temperature of at least 100° C. before undergoing grinding and classification, are gradually being replaced by chemical production methods such as emulsion polymerization aggregation methods and suspension polymerization methods, in which toner production is conducted at a temperature no higher than 100° C., and which enable more precise control of the toner powder properties such as the toner particle size and structure than conventional mix-and-grind methods.
However, these chemical production methods yield toners in which the quantity of residual volatile organic compounds is considerably higher than in toners produced by conventional mix-and-grind methods, meaning that after extended use, or in high-speed electrophotographic systems that require high-temperature fixation, contamination inside the machine caused by these volatile organic compounds can lead to a variety of problems, including deterioration in the system quality, shortening of the system lifespan, reduction in the recyclability of various components, and odors caused by diffusion of these volatile materials into the atmosphere outside the machine, and these problems are the focus of considerable attention. The odor problem becomes particularly noticeable in smaller offices, such as cases where high-speed copying or printing is conducted in a SOHO environment. The odors that are generated diffuse through the atmosphere, and are detected as an offensive odor upon exceeding the odor threshold. From an ergonomic viewpoint, acceptable levels for these offensive odors are evaluated on the basis of statistical analyses of factors such as physiological aversion (irritation and offensiveness) and reduction in work efficiency.